Grate-bar construction



July 8, 1930. HQWLE 1,769,996-

GRAIE BAR C ONS TRUCT ION Filed March 2, 192"! lllmi INVENTOR WLW WL ATTORNEYS E0. Hon/LE.

Patented July 8, 1930 UNITED-STATES PATENT ,oF IcE ERNEST 0. I-IOWLE, on cnioAsqiLLnvors, ASSIGNQB, BY MESNE ASSIGNMENTS, ro MID-WEST INGINERATOR CORPORATIOBL'OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE Application filed March 2 'constructions, and arrangements herein described and claimed. a

7 An object of the invention is to provide a grate bar of the step grate type which is not subject to the warping an'dburning of the 19 step bar grate of the ordinary type.

A further object is to provide a grate bar construction in which there is a greater radiating surface and in which expansion is provided for, thereby obviating the danger of buckling or warping.

A further object is to provide a grate bar construction of the step grate type which is so arranged that air spaces are provided between the upper surface of the grate and the 20, burning mass which it supports, thus further tending to keep thegrate in a cooled condition and preventing its burning.

Other objects and advantages will appear in the following specification, and the novel 5 features of the invention will be particularly pointed out in the appended claims.

My invention is illustrated in the accompanying drawings, forming part of this application, in which Figure l is a front view of a grate bar in its normal inclined position,

7 Figure 2 is a side view of the bar shown in Figure 1,

Figure 3 is a diagrammatic View showing 3,5 the position of the bar in an incinerator, and

Figure 4 is a horizontalsection through an incinerator, .showlng the arrangement of a plurality of bars.

In carrymg out my lnvention, I make use 9;:0f a series of bars, such as that shown in the drawings. These bars, as will be noted, consist of a central supportlng portion or stringer 1 'andintegral steps 2 which project laterally on either side of the stringer, the steps -5. :and central stringer being reinforced by integral brace members 3 which-serve to prevent warping of thesteps and central stringer. As will be seen from Figure 2, the steps are parallel and when the bar is in ltS'l'lOIIIlHil.

50,; position theyare horizontal. 'Near the top 'GBATE-BAR CONSTRUCTION A 1927. Serial No. 172,096.

of the grate bar is a step 2 which is inclined i so as to permit the material fed into the furnace to slide downwardly on the grate bar. This construction permits the upper ends of the bars to be positioned relatively-close to the furnace wall, avoidsthe use of theusual apron to overlap the upper ends of the bars, and permits a grate bar to be" readily removed or replaced through the fire door; of the furnace. The bcttomportion ofthebar is projected downwardly and is provided with a recess 4.

In Figure 3 I have shown how the bar rests] at its upper end on any suitable support;

ing member, such as the plate 5 carried by the, 5

wall f the incinerator. At the bottom, the grate bars are supported on a transverserod. or plate 7 having an upstanding rounded portion8arranged to be received in the re-- cess 4:. It will be observed that there is an auxiliary grate portion 9; below the step grate. This auxiliary portion, however, is ordinary and forms no part of the present-in Vention. In Figure 4-. I have shown how the bars of thestep grate are arranged. The upper end of thestringer is designedto restin a recess 5 in the supporting member 5. The bars are spaced slightl apart, as shown at 10, and the bars at the side are also spaced'slightly from the wall 6 of the incinerator or furnace. Frorn the foregoing description of the Va-. rious parts of the deviee, the operation there-1 of maybe readily understood. I'ni the ordig nary step grate construction, thesteps are generally loosely carried on side stringers and expand When subjected to heat and warp; out of, shape or crack and buckle up;

The integral construction of the present step grate, in which the steps extend from the front to the: rear of'the grate bar, gives increased radiating surface and thus tends to keep the grate cool; It provides space, for the admission of air between the stepscinto the body of the, burning mass upon the grate. v It will be noted thatbetween'the front edges of the successive steps the frontedge of the stringer is cut away, as, shown at: '11.

his tend t0 pr vid n a r. rase etwe n theburning m s 11ml t a-r itelf which tends tofurther cool the grate i In Figure-4:, it will be seen that room is provided for the lateralexpansion of the steps so that the grate bars are not buckled as they might bewhere such free expansion is not provided for. Longitudinal expansion of the baris also provided for, and to this endthe upper supporting member 5 is notched so asto hold thegrate in position but to' permit such expansion.

recess in which the upper end of the stringer is held against rotational andlateral movelnents but with capacity for longitudinal sliding inovement'to compensate for longi tudinal expansion thereof. g

* ERNEST O HOWLE.

In Figure 8, in which I haveshown a diagrammatic view of the incinerator, the matter i is deposited on; the grate either through the door 12 or it nay be deposited from above through anupperopening,'not" shown. *Thef uppermost step 2 tends to g'uidethe n aterialextensions carried by the stringer'to constitute steps and extending from the front to the rear of said central stringer, said stringer being cut away between the side extensions for forming "recesses, and integral brace m embersfor reinforcing the side extensions and the central stringer, apair of said in- V tegral' side extensions "being inclined in the direction of the other of said side extensions and the otherof said side extensions being arranged in parallelisnr, a r 2. A grate bar adapted to be supported in an; inclined position comprising-a centralstringer, a series "iof -spaced-apart integralside extensions carried by the stringer to con-1 cesses to provide draft passages between' the stringer and the Inaterialibeing burned, re

stringer-being formed with; an upper end portion of rectangular configuration iii-cross I stitute steps, said stringer being cut-away between the side extensions for forming re-g infor cing" Webs formed integrally with the side extensions and the central stringer, the

section,theflower end-ofsaid central stringer I I recess for holding the upper end of the stringer against rotationbut withcapacityfor Ion gitud-inal}slidinginovement. i .3. A-grate bar'co'nstruction comprising a "central stringer', a seriesof side extensions formed integrally with the-stringer and con-v @Stituting a seriesof steps across which the; i

. 9 material. fed into the furnace moves down- Wardly toward the (lower end, of the said i gratefbar, the' lower'end of saidv centralr r n er' i is urp fi d a n lbhgitiidtf I v v 65 5 f pwnward'movement, supporting neans for the upper end of the bar "having guiding being provided with a recess,- means substantially conforming to the'shape of said last namedrecess forsupporting the lower end of i r I said stringer, and means having afiguiding 

